Iran’s most powerful authority, Ayatollah Ali Khamenei, said on Thursday the United States was using a chemical attack in Syria’s civil war as a pretext to interfere in the country and warned it would suffer loss from any intervention.

“In the case of Syria, the chemical attack is a pretext… The Americans try to play with words and pretend that they’ve become involved in this case for humanitarian aims,” Khamenei told a meeting of the Assembly of Experts, a state body.

“I believe the Americans are making mistakes in Syria and they have felt the impact and will certainly suffer loss,” he said in the speech, whose text was published on his official website.